- MaterializeExpr can never be formed in an argument list (but
still can as the base object) so remove that case from CSApply.
- LValues never exist *inside* of tuples, so remove code related
to that.
Swift SVN r11889
- Change the AST for get/set functions to take self @inout only when they
are @mutating. Setters default to @mutating, but can be explicitly marked
@!mutating. Getters default to not mutating, but can be marked @mutating.
This causes self to follow.
- Change sema to handle semantic analysis of a.y (and subscripts) based on
whether the computed type of a allows mutation (which is when 'a' is an
lvalue, or both the getter and setter are non-mutating). When both of
these conditions fail, 'a.y' has rvalue type, and is thus non-mutable.
- Rework silgen of lvalues to handle this: now properties and subscripts
can have rvalues as bases, which means that all the lvalue machinery needs
to be able to handle the full generality of base expressions (which is
what my recent patches have been paving the way towards).
- Rework silgen of rvalues to similarly handle rvalue bases.
- Rework silgen of both to handle the case where the AST has found a base
expression that is an lvalue, but where only a non-mutating getter or
setter is needed. Right now, we just emit a load of the lvalue, but
it would result in better code to not require the base be an lvalue at
all (todo).
The upshot of all of this is that we are doing *much* less AST-level
materialization (MaterializeExpr goes down), we generate a lot better SIL
out of SILGen in many cases, and 'self' being an rvalue in properties and
subscripts means that we correctly reject code like the examples in
test/Sema/immutability.swift.
Swift SVN r11884
I originally wrote to turn "loadexpr(declrefexpr(letdecl))" is dead, remove
it. Let decls are now always rvalues, so they never are loaded.
Swift SVN r11804
is no longer an lvalue, since it doesn't make sense to assign to super.
This eliminates a bunch of special cases and simplifies things.
Swift SVN r11803
- Introduce a new TypeBase::getInOutObjectType() that strips off @inout types
- Switch stuff that is calling getRValueType() to call getInOutObjectType()
when they are stripping @inout, not @lvalue (this is primarily around
stuff working with self)
- Update testcases, some diagnostics improve around & handling.
This fixes rdar://15708430 and rdar://15729093.
Swift SVN r11794
to to @lvalue bases instead of @inout bases, and make the verifier
check that the right type is being used consistently.
Before:
(member_ref_expr type='@lvalue (E0, E1)' ...
(address_of_expr implicit type='@inout ZipGenerator2<E0, E1>'
(declref_expr implicit type='@lvalue ZipGenerator2<E0, E1>'
After:
(member_ref_expr type='@lvalue (E0, E1)' ...
(declref_expr implicit type='@lvalue ZipGenerator2<E0, E1>'
Swift SVN r11792
This allows them to appear in argument lists of functions, enabling behavior
like this:
func test_arguments(a : Int, var b : Int, let c : Int) {
a = 1 // ok (for now).
b = 2 // ok.
c = 3 // expected-error {{cannot assign to the result of this expression}}
}
Swift SVN r11746
with qualifiers on it, we have two distinct types:
- LValueType(T) aka @lvalue T, which is used for mutable values on the LHS of an
assignment in the typechecker.
- InOutType(T) aka @inout T, which is used for @inout arguments, and the implicit
@inout self argument of mutable methods on value types. This type is also used
at the SIL level for address types.
While I detangled a number of cases that were checking for LValueType (without checking
qualifiers) and only meant @inout or @lvalue, there is more to be done here. Notably,
getRValueType() still strips @inout, which is totally and unbearably wrong.
Swift SVN r11727
build MaterializeExpr with an implicit lvalue type. In the case when materialization
is still needed, we now produce addressof(materializeexpr(rvalue)) instead of producing
materializeexpr(rvalue) with @inout type.
Verify this in the AST verifier.
Swift SVN r11717
- Switch all the 'self' mutable arguments to take self as @inout, since
binding methods to uncurried functions expose them as such.
- Eliminate the subtype relationship between @inout and @inout(implicit),
which means that we eliminate all sorts of weird cases where they get
dropped (see the updated testcases).
- Eliminate the logic in adjustLValueForReference that walks through functions
converting @inout to @inout(implicit) in strange cases.
- Introduce a new set of type checker constraints and conversion kinds to properly
handle assignment operators: when rebound or curried, their input/result argument
is exposed as @inout and requires an explicit &. When applied directly (e.g.
as ++i), they get an implicit AddressOfExpr to bind the mutated lvalue as an
@inout argument.
Overall, the short term effect of this is to fix a few old bugs handling lvalues.
The long term effect is to drive a larger wedge between implicit and explicit
lvalues.
Swift SVN r11708
- mark closure arguments (both explicit and $0's) as immutable
- Adjust the stdlib (one place) and some tests to cope with this.
- Remove some special case logic in sema for lvalue qualifying
anonymous closure exprs, which is now the wrong thing to do.
Swift SVN r11674
- In AST/Decl.cpp, simplify by always setting isMutating to true for
ctors/dtors, since mutability only means something to struct/enum
methods anyway.
- in DeclContext.cpp, continue to lvalue qualify the 'self' of protocol
methods, this is currently dead.
- in CSApply, fix logic for some value-type member processing stuff
to properly handle methods that have a self which is not lvalue
qualified. Not exercised yet.
Swift SVN r11650
struct rvalue, to produce a struct element directly, without converting the rvalue
to an lvalue.
This means that it no longer materializes an lvalue when applied to a let declaration
or other rvalue. For example, this testcase:
struct X { var a,b : Int}
func g() -> X { return X(1,2) }
func f() {
let a = g().a
}
used to sema into:
(load_expr implicit type='Int'
(member_ref_expr type='@inout (implicit, nonsettable)Int' decl=t.(file).X.a@t.swift:2:16
(materialize_expr implicit type='@inout (implicit)X'
(call_expr type='X'
and silgen into:
%1 = function_ref @_TF1t1gFT_VS_1X : $@thin () -> X // user: %2
%2 = apply %1() : $@thin () -> X // user: %4
%3 = alloc_stack $X // users: %7, %5, %4
store %2 to %3#1 : $*X // id: %4
%5 = struct_element_addr %3#1 : $*X, #a // user: %6
%6 = load %5 : $*Int64
It now sema's into:
(member_ref_expr type='Int' decl=t.(file).X.a@t.swift:1:16
(call_expr type='X'
and silgens into:
%1 = function_ref @_TF1t1gFT_VS_1X : $@thin () -> X // user: %2
%2 = apply %1() : $@thin () -> X // user: %3
%3 = struct_extract %2 : $X, #a
I think I'm finally starting to grok Doug's crazy typechecker magic.
Swift SVN r11599
(various) FunctionType::get's, ArrayType::get,
ArraySliceType::get, OptionalType::get, and a few
other places.
There is more to be done here, but this is all I plan to do
for now.
Swift SVN r11497
Similar to r11235, but for 'is' expressions. QoI suffers somewhat here
because (1) we don't have an easy way to specialize the diagnostic,
and (2) we can't fix up the broken constraint system when we hit a
problem.
Swift SVN r11241
Previously, we had an artificial separation between the subexpression
"x" and the context of the expression "x as T". This breaks down when
the subexpression includes a reference to an anonymous closure
argument (e.g., $0) from a single-expression closure. By merging the
systems, we fix the crasher (<rdar://problem/15633178>) and allow
improved type inference for these expressions.
Swift SVN r11235
Notice that I'm hacking the test to get it running again. I'd normally
feel bad about this, but since labeled tuple elements are going away,
the class of problems this commit is working around will disappear
entirely.
Swift SVN r11115
